<?php
/**
 * Zend Framework
 * LICENSE
 * This source file is subject to the new BSD license that is bundled
 * with this package in the file LICENSE.txt.
 * It is also available through the world-wide-web at this URL:
 * http://framework.zend.com/license/new-bsd
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to license@zend.com so we can send you a copy immediately.
 * @category Zend
 * @package Zend_Filter
 * @copyright Copyright (c) 2005-2012 Zend Technologies USA Inc. (http://www.zend.com)
 * @license http://framework.zend.com/license/new-bsd New BSD License
 * @version $Id: StringTrim.php 24593 2012-01-05 20:35:02Z matthew $
 */
/**
 *
 * @see Zend_Filter_Interface
 */
require_once 'Zend/Filter/Interface.php';

/**
 *
 * @category Zend
 * @package Zend_Filter
 * @copyright Copyright (c) 2005-2012 Zend Technologies USA Inc. (http://www.zend.com)
 * @license http://framework.zend.com/license/new-bsd New BSD License
 */
class Zend_Filter_StringTrim implements Zend_Filter_Interface {

    /**
     * List of characters provided to the trim() function
     * If this is null, then trim() is called with no specific character list,
     * and its default behavior will be invoked, trimming whitespace.
     * @var string null
     */
    protected $_charList;

    /**
     * Sets filter options
     * @param string|array|Zend_Config $options
     * @return void
     */
    public function __construct ($options = null) {
        if ($options instanceof Zend_Config) {
            $options = $options -> toArray ();
        } else 
            if ( ! is_array ($options)) {
                $options = func_get_args ();
                $temp['charlist'] = array_shift ($options);
                $options = $temp;
            }
        if (array_key_exists ('charlist', $options)) {
            $this -> setCharList ($options['charlist']);
        }
    }

    /**
     * Returns the charList option
     * @return string null
     */
    public function getCharList () {
        return $this -> _charList;
    }

    /**
     * Sets the charList option
     * @param string|null $charList
     * @return Zend_Filter_StringTrim Provides a fluent interface
     */
    public function setCharList ($charList) {
        $this -> _charList = $charList;
        return $this;
    }

    /**
     * Defined by Zend_Filter_Interface
     * Returns the string $value with characters stripped from the beginning and end
     * @param string $value
     * @return string
     */
    public function filter ($value) {
        if (null === $this -> _charList) {
            return $this -> _unicodeTrim ((string) $value);
        } else {
            return $this -> _unicodeTrim ((string) $value, $this -> _charList);
        }
    }

    /**
     * Unicode aware trim method
     * Fixes a PHP problem
     * @param string $value
     * @param string $charlist
     * @return string
     */
    protected function _unicodeTrim ($value, $charlist = '\\\\s') {
        $chars = preg_replace (array('/[\^\-\]\\\]/S', '/\\\{4}/S', '/\//'), array('\\\\\\0', '\\', '\/'), $charlist);
        $pattern = '^[' . $chars . ']*|[' . $chars . ']*$';
        return preg_replace ("/$pattern/sSD", '', $value);
    }

}
